Dilated cardiomyopathy (DCM) is a form of heart disease seen most commonly in large breed dogs. However, it can be seen in dogs of any breed, both large and small.
Dilated cardiomyopathy is a disease in the muscle of the heart that ultimately results in heart failure for affected dogs.
Many cases of dilated cardiomyopathy are thought to be genetic in origin. However, others may be caused by nutritional imbalances or abnormalities, infectious diseases or other causes.
Medications Used to Treat Dilated Cardiomyopathy in Dogs
There are several medications that are regularly used to treat dogs suffering from heart disease and/or heart disease as a result of dilated cardiomyopathy.
- If congestive heart failure is present, furosemide (Lasix®) is used. Furosemide is a diuretic that is used to remove excess fluid from body tissues. In some cases, other diuretics, such as spironolactone and hydrochlorothiazide, may be used in conjunction with furosemide. This is most common when furosemide by itself is not completely effective.
- Angiotensin-converting enzyme inhibitors (ACE inhibitors) are frequently used as well. These medications dilate the blood vessels, making it easier for the heart to pump blood through the body. They can also help control elevated blood pressure. Commonly used ACE inhibitors include enalapril and benazepril.
- Pimobendan (Vetmedin®) is a medication that dilates blood vessels and also helps make the heart muscle contract more efficiently.
- Digoxin and digitoxin are both inotropes (medications that help the heart muscle to contract more efficiently). These medications are also used to treat some types of arrhythmias as well. However, the risk of side effects and toxicity with digoxin and digitoxin is high. Newer medications which accomplish the same effects may be a better choice for many dogs with heart failure than these medications.
- When arrhythmias are present, they may need to be controlled with beta-blockers (such as atenolol or propanolol) or calcium channel blockers (such as diltiazem.)
- When nutritional deficiencies are suspected (or confirmed), nutritional supplements are used. Some dogs are treated with these supplements even when nutritional deficiencies are not suspected, though their efficacy in these cases is open for debate. Commonly used supplements include taurine, L-carnitine and enzyme CoQ10 (an antioxidant.)
Other Techniques Used to Treat Canine Heart Disease Caused by Dilated Cardiomyopathy
When fluid builds up in the abdominal cavity or in the chest cavity, it may need to be physically removed. This is termed abdominocentesis when the fluid is removed from the abdominal cavity. When the fluid is located in the chest cavity, the procedure is termed thoracocentesis.
Prognosis for Dogs with Dilated Cardiomyopathy
The prognosis for dogs diagnosed with dilated cardiomyopathy depends on many different factors. These factors include the breed of dog, the specific type of dilated cardiomyopathy that is involved and the severity of existing clinical signs.
Dilated cardiomyopathy is generally a progressive disease. In some cases, it may progress slowly and the affected dog may live for months to years. However, in some breeds (particularly Dobermans), sudden death may occur even without signs of congestive heart failure.